1. Field of the Invention
The present invention relates to a method and device for storing and retrieving inflected forms of words in electronic reference products and, in particular, in electronic dictionaries, electronic bilingual dictionaries, electronic thesauri and an electronic Bible. In a particular form of the invention, the storing and retrieving of inflected information in an English/Spanish electronic dictionary is encompassed.
2. Inflected Forms of Language
Inflected forms of a word encompass all of its variations in usage. Examples of inflected forms are the plural forms of English nouns, the comparative (`er`) and superlative forms (`est`) forms of English adjectives, the past tense of English verbs, and so on. Different languages inflect differently. English typically only distinguishes between 5 different forms of a verb (infinitive, past, past participle, present participle, 3rd person singular), whereas Spanish verbs have about 50 different forms.
More specifically, the different forms of green are green, greener and greenest. The forms of go are go, went, gone, going, and goes. The forms of play are play, played, playing and plays. (Note that different forms of a word may overlap). Also, some words may not allow certain forms. The forms of `mere` are `mere` and `merest`; there is no `merer` (meaning more `mere`).
3. Background Prior Art
Certain known electronic reference products utilize a technique to store words called the directed acyclic word graph (DAWG). Such technique is described in the article "Sorting and Searching", Vol. 3 of the series, "The Art of Computer Programming", by Donald Knuth, 1973, Addison Wesley (p. 481 ff.). While Knuth uses the term, "trie", the term DAWG is now standard. Such DAWGs have been used to store certain word-related information in the past. The present invention uses the DAWG structure as a starting point, but modifies it in a number of unique ways to provide the ability to store and retrieve inflected information.